International Journal of Technical Innovation in Modern Engineering & Science (IJTIMES) Impact Factor: 3.45 (SJIF-2015), e-ISSN: 2455-2585 Volume 3, Issue 07, July-2017
FENDER SYSTEMS AND THEIR AFFECT ON BERTHING STRUCTURES WITH SPECIAL MENTION TO IS:4651, BS:6349 AND PIANC GUIDELINES Santosh R. Chaurasiya1, Dr.A.A.Bage2, Dr.V.S.Joshi3 1 2
Structural Engineering department, Sardar Patel College of Engineering, Structural Engineering department, Sardar Patel College of Engineering, 3 Afcons Infrastruture Limited,
Abstract—Water transport is the cheapest and the oldest mode of transport. It operates on a natural track and hence does not require huge capital investment in the construction and maintenance of its track except in case of canals. During the last decades ships have grown larger and larger and the draft of the ship has also increased. Up to now, reliable, theoretically founded design criteria are hardly available. The lack of good design criteria is the prime reason for making researches into the possibilities of an experimental and theoretical determination of berthing forces. A jetty, two design vessels and four different types of fender systems are taken into consideration. The Berthing Energy is evaluated using IS:4651, BS:6349 and PIANC “Guidelines for Design of Fender Systems, 2002” for the largest and smallest vessel. The minimum Berthing Energy from the design vessels is obtained by using the three codes. Using the minimum Energy, the reactions developed for various fender systems is obtained. Based on those values, the fender system best suited for the jetty is found. Using those values, the Jetty is analysed and the Bending Moments developed in the structure for four fenders are considered. For modelling of jetty, STAAD.Pro is used. Keywords: Berthing Energy, Reactions, Fender System, Bending Moments, STAAD.Pro. I.
INTRODUCTION
Water transport has the largest carrying capacity and is most suitable for carrying bulky goods over long distances. It has played a very significant role in bringing different parts of the world closer and is indispensable to foreign trade. Ports, terminals and harbours play a key role in the shipment of goods around the globe. There are two types of water transport viz. Inland water transport and Ocean-transport. In the late fifties, conditions suddenly changed. Not only did the draft of ships double in less than twenty years, but the mass increased ten times more from a maximum of 50,000 tons to 5,00,000 tons. Now the new ships required deeper water so that they could be berthed. Not all the ports all over the world facilitate berthing of larger ships. In such cases the larger ship halt at a distance of certain nautical miles from the shore in the sea or ocean and the cargo or the goods are unloaded into smaller ships also known as barges which carry the cargo to the coast. This operation may be economical depending upon many factors like the material which is transported, cost of navigation using barges, etc. Now these small ships are berthed at the port and goods are unloaded from the barges. For ports with deep waters the larger ships are directly berthed at the ports. Berths should accommodate the largest design ships, but they must also cater for small and intermediate ships. Generally a berthing facility consists of one or more elastic elements (fenders) attached to a rigid structure (finger pier, caisson-type jetty, quay-wall, etc.). The fenders absorb the berthing forces and form a protection for ship and berthing structure. As the maximum permissible berthing force against the side of e.g. a mammoth tanker is distinctly lower than what is acceptable for the berthing structure, the ship is therefore the prevailing factor for fender design. They are first and foremost a safety barrier to protect people, ships and structures. Most fender systems use elastomeric (rubber) units, air or special foams which act as springs to absorb the ship’s kinetic energy The phenomenon occurring during the berthing manoeuvre of a ship are complicated and the fender loads are influenced by a lot of parameters: the configuration of the berthing site, the geometry and the rigidity or hull of the ship, the mechanical properties of the fenders, the speed of approach, the forces exerted by tugs, wind, current and waves, the mode of motion, the keel clearance.
II. CODAL PROVISIONS A. As per IS: 4651 (Part III) - 1974 When an approaching vessel strikes a berth, a horizontal force acts on the berth. The magnitude of this force depends on the kinetic energy that can be absorbed by the fendering system. The reaction force for which the berth is to be designed
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